On 2016-04-14 22:05, Rainer Jung wrote: > Am 14.04.2016 um 22:05 schrieb olli hauer: >> On 2016-04-14 21:48, Yann Ylavic wrote: >>> On Thu, Apr 14, 2016 at 9:40 PM, olli hauer <[email protected]> wrote: >>>> I've done a quick test with >>>> $ ab -n 10000 -c 100 $host/$url >>>> >>>> During the test the count of idle worker are incrementing and decrementing >>>> but it ab has finished the requests the count of idle workers stays on the >>>> last highest count ... >>> >>> This looks normal to me, did the bahaviour changed w.r.t. 2.4.19? >>> >>> When the stress is running, the number of idlers (workers that do >>> nothing) fluctuates, according to the number of connections/requests >>> and children created to sustain the load. >>> >>> When the load stops, the number of idlers increases, and won't >>> decrease unless MaxSpareThreads is reached (i.e. children are stopped, >>> each releasing ThreadsPerChild idlers). >>> >> >> Ah, OK this will explain the numbers. >> Unluckily I haven't looked to scoreboard with 2.4.19, but give me some >> minutes ... > > Not that important for the current discussion, but please note that "ab" does > not use Keep-Alive connections by default. If you want to use HTTP > Keep-Alive, add "-k". > > Without it you create many new connections per second (depending on > throughput this can easily be more than 1000 connections per second) which > are only used very shortly (one request) and after shutting down they might > end up in TIME_WAIT and stay there e.g. for a minute depending on OS details > (you can check via "netstat"). Once you get more than a few thousand > connections in TIME_WAIT, TCP/IP could get slower. Thus "ab -k" will often > result in more stable behavior. >
Hi Rainer, Thanks for the hint! (indeed without -k I can simulate the svnstat tool that pulled my svn servers down) I've done some tests with 2.4.19 there is maybe an interesting detail. With 2.4.19 the last request is empty for an idle worker, with 2.4.20 not (shows the client, proto, Vhost and request) I've attached the results as .txt file. -- olli
httpd some seconds after start: --------------------------------------------- Server MPM: event Server Built: Apr 14 2016 22:02:14 Current Time: Thursday, 14-Apr-2016 22:03:24 CEST Restart Time: Thursday, 14-Apr-2016 22:03:08 CEST Parent Server Config. Generation: 1 Parent Server MPM Generation: 0 Server uptime: 16 seconds Server load: 1.21 0.69 0.66 Total accesses: 0 - Total Traffic: 0 kB CPU Usage: u0 s0 cu0 cs0 0 requests/sec - 0 B/second - 1 requests currently being processed, 74 idle workers PID Connections Threads Async connections total accepting busy idle writing keep-alive closing 56486 0 yes 0 25 0 0 0 56487 0 yes 0 25 0 0 0 56488 0 yes 1 24 0 0 0 Sum 0 1 74 0 0 0 during ab test --------------------------------------------- Current Time: Thursday, 14-Apr-2016 22:04:14 CEST Restart Time: Thursday, 14-Apr-2016 22:03:08 CEST Parent Server Config. Generation: 1 Parent Server MPM Generation: 0 Server uptime: 1 minute 6 seconds Server load: 12.23 3.14 1.53 Total accesses: 7868 - Total Traffic: 1.8 MB CPU Usage: u86.8047 s1.15625 cu0 cs0 - 133% CPU load 119 requests/sec - 28.2 kB/second - 242 B/request 78 requests currently being processed, 97 idle workers PID Connections Threads Async connections total accepting busy idle writing keep-alive closing 56486 4 yes 1 24 0 0 0 56487 7 yes 7 18 0 0 0 56488 10 yes 8 17 0 0 1 56506 10 yes 3 22 0 0 7 56560 25 yes 24 1 0 0 1 56561 5 yes 14 11 0 0 0 56562 8 yes 21 4 0 0 0 Sum 69 78 97 0 0 9 some time after ab finished --------------------------------------------- Current Time: Thursday, 14-Apr-2016 22:06:59 CEST Restart Time: Thursday, 14-Apr-2016 22:03:08 CEST Parent Server Config. Generation: 1 Parent Server MPM Generation: 0 Server uptime: 3 minutes 51 seconds Server load: 1.17 2.09 1.39 Total accesses: 10011 - Total Traffic: 2.5 MB CPU Usage: u109.742 s1.46094 cu0 cs0 - 48.1% CPU load 43.3 requests/sec - 10.9 kB/second - 257 B/request 1 requests currently being processed, 174 idle workers PID Connections Threads Async connections total accepting busy idle writing keep-alive closing 56486 0 yes 0 25 0 0 0 56487 0 yes 1 24 0 0 0 56488 0 yes 0 25 0 0 0 56506 0 yes 0 25 0 0 0 56560 0 yes 0 25 0 0 0 56561 0 yes 0 25 0 0 0 56562 0 yes 0 25 0 0 0 Sum 0 1 174 0 0 0 2.4.20 with patch: -------------------------- Srv PID Acc M CPU SS Req Conn Child Slot Client Protocol VHost Request 0-0 31501 0/125/125 R 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/122/122 _ 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/132/132 R 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/125/125 _ 35.56 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/126/126 _ 35.56 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/122/122 _ 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/126/126 R 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/129/129 R 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/132/132 R 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/132/132 _ 35.56 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 0-0 31501 0/126/126 R 35.96 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 ..... 6-0 31581 0/135/135 R 38.90 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 6-0 31581 0/146/146 R 38.90 0 0 0.0 0.03 0.03 $client http/1.1 $host:443 GET /server-status/ HTTP/1.0 2.4.19 -------------------------- Srv PID Acc M CPU SS Req Conn Child Slot Client Protocol VHost Request 0-0 56486 0/43/43 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/50/50 _ 13.37 160 0 0.0 0.01 0.01 0-0 56486 0/43/43 _ 13.10 160 0 0.0 0.01 0.01 0-0 56486 0/47/47 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/49/49 _ 13.37 160 0 0.0 0.01 0.01 0-0 56486 0/47/47 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/52/52 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/49/49 _ 13.10 160 0 0.0 0.01 0.01 0-0 56486 0/49/49 _ 13.09 160 0 0.0 0.05 0.05 0-0 56486 0/57/57 _ 13.38 160 0 0.0 0.01 0.01 0-0 56486 0/50/50 _ 13.37 160 0 0.0 0.01 0.01 0-0 56486 0/49/49 _ 13.38 160 0 0.0 0.01 0.01 0-0 56486 0/53/53 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/46/46 _ 13.37 160 0 0.0 0.01 0.01 0-0 56486 0/41/41 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/51/51 _ 13.37 160 0 0.0 0.01 0.01 0-0 56486 0/44/44 _ 13.10 160 0 0.0 0.01 0.01 0-0 56486 0/47/47 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/51/51 _ 13.38 160 0 0.0 0.01 0.01 0-0 56486 0/47/47 _ 13.38 160 0 0.0 0.01 0.01 0-0 56486 0/48/48 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/50/50 _ 13.37 160 0 0.0 0.01 0.01 0-0 56486 0/45/45 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/45/45 _ 13.11 160 0 0.0 0.01 0.01 0-0 56486 0/37/37 _ 13.11 160 0 0.0 0.01 0.01 1-0 56487 0/65/65 _ 17.50 160 0 0.0 0.01 0.01 1-0 56487 0/64/64 _ 17.51 160 0 0.0 0.01 0.01 1-0 56487 0/63/63 _ 17.50 160 0 0.0 0.01 0.01 1-0 56487 0/63/63 _ 17.50 160 0 0.0 0.01 0.01 1-0 56487 0/59/59 _ 17.50 160 0 0.0 0.01 0.01 1-0 56487 0/62/62 _ 17.51 160 0 0.0 0.01 0.01 1-0 56487 0/66/66 R 17.51 0 0 0.0 0.01 0.01 $client http/1.1 $host:443 GET /server-status/ HTTP/2 1-0 56487 0/66/66 _ 17.50 160 0 0.0 0.01 0.01 1-0 56487 0/58/58 _ 17.50 160 0 0.0 0.01 0.01 1-0 56487 0/66/66 _ 17.51 160 0 0.0 0.01 0.01
